Patent · US Expired

Optical information recording and reproducing apparatus with tracking control by sampling

US4847822A · kind A · utility

4Cited by
1References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 9, 1987
Grant dateJul 11, 1989
Priority date
Expiry dateJul 9, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B7/0948
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An optical information recording and reproducing apparatus of a sampling servo system which effects the tracking by holding the differential output of the reproduced signals of tracking pits that are wobbled toward the right and left relative to the track of the optical disk. Reproduced signals of a plurality of pits arranged maintaining a distance on the track and wobbled toward the right or left in a servo signal region, are compared with each other to detect any abnormal condition in the tracking pits. When the abnormal condition is detected, the tracking signal that is sampled is not used, but instead the tracking signal sampled under the normal condition is continuously used to perform the tracking control.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.